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A New Instrument for Balloon-Borne In Situ Aerosol Size Distribution Measurements, the Continuation of a 50 Year Record of Stratospheric aerosols Measurements

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JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES 2022年第24期127卷 e2022JD037485-e2022JD037485页

作者： Kalnajs, Lars E. Deshler, Terry Univ Colorado Lab Atmospher & Space Phys Boulder CO 80309 USA

Profiles of stratospheric aerosol size distributions have been measured using balloon-borne in situ optical particle counters, from Laramie, Wyoming (41 degrees N) since 1971. In 2019, this measurement record transitioned to the Laboratory for Atmospheric and Space Physics (LASP) in Boulder, Colorado (40 degrees N). The new LASP Optical Particle Counter (LOPC), the fourth generation of instruments used for this record, is smaller and lighter (2 kg) than prior instruments, measures aerosols with diameters >= 0.3-30 mu m in up to 450 size bins, with a flow rate of 20 L min(-1). The improved size resolution enables the complete measurement of size distributions, and calculation of aerosol extinction without fitting a priori distribution shapes. The higher flow provides the sensitivity required to measure super-micron particles in the stratosphere. The LOPC has been validated against prior Wyoming OPCs, through joint flights, laboratory comparisons, and statistical comparisons with the Wyoming record. The agreement between instruments is generally within the measurement uncertainty of +/- 10%-20% in sizing and +/- 10% in concentration, and within +/- 40% for calculated aerosol moments. The record is being continued with balloon soundings every 2 months from Colorado, coordinated with measurements of aerosol extinction from the SAGE III instrument on the International Space Station. Comparisons of aerosol extinction from the remote and in situ platforms have shown good agreement in the stratosphere, particularly for wavelengths < 755 nm and altitudes < 25 km. For extinction wavelengths > 1,021 nm and altitudes above 25 km SAGE III/International Space Station extinction has a low bias relative to the in situ measurements, yet still within the +/- 40% uncertainty.

关键词： aerosols instrumentation validation

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Copper acetate aerosols: A possible tool complementary to vaccination in fight against SARS-CoV-2 and variants replication

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MEDICAL HYPOTHESES 2022年 160卷 110775-110775页

作者： Deloncle, Roger Guillard, Olivier Pineau, Alain Lesage, Gerard Tours Univ Sch Pharm F-37200 Tours France Poitiers Univ Sch Med & Pharm F-86022 Poitiers France Nantes Univ Sch Pharm F-44035 Nantes 1 France

In SARS-CoV-2, at the S1/S2 furin cleavage site, a four amino acid insert (P-R-R-A) not found in closely related corona viruses, has been shown to facilitate entry into respiratory epithelial cells and promote virus transmission, infectivity and virulence. By cupric aerosol treatment, complexation of these four amino acids (-P-R-R-A-), at the spike (S) protein site will lead to a conformational change possibly impeding SARS-CoV-2 replication process in the respiratory track. Since these four amino acids yield strong and stable copper complexes, subsequent to a steric hindrance, this complexation will disturb the furin-like protease cleavage at the spike protein site as it has been recently shown in vitro with copper gluconate. The compilation of stability constants for copper amino-acid complex formation, showing values of the same order of magnitude for all the twenty proteinogenic amino-acids demonstrate thermodynamically that copper amino-acid chelation for SARS-CoV-2 virus will not be affected by mutations leading to amino acid exchanges in the spike protein region. Given its low toxicity, and its very low stability formation constant, copper acetate is proposed rather than copper gluconate for possible cupric aerosol or nasal spray treatments aimed at impeding SARS-CoV-2 multiplication. It will open different medical perspectives, complementary to vaccination, in the fight against COVID 19 native virus, variants and future mutants.

关键词： COVID 19 SARS-CoV-2 variants aerosols Amino acids complexes Copper acetate Nasal sprays

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Impact of aerosols on warm clouds over the Sichuan Basin, China in winter based on the MERRA-2 reanalysis dataset

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ATMOSPHERIC POLLUTION RESEARCH 2022年第3期13卷

作者： Zhu, Shaobin Xiao, Zhisheng Che, Huizheng Chen, Quanliang Chengdu Univ Informat Technol Sch Atmospher Sci Plateau Atmospher & Environm Key Lab Sichuan Prov Chengdu 610225 Peoples R China Chinese Acad Meteorol Sci State Key Lab Severe Weather LASW Beijing 100081 Peoples R China Chinese Acad Meteorol Sci Key Lab Atmospher Chem CMA Beijing 100081 Peoples R China Nanjing Univ Informat Sci & Technol Sch Atmospher Phys Nanjing 210044 Peoples R China

The impacts of aerosols on low warm clouds over the Sichuan Basin are still not well understood. We used the long-term Modern-Era Retrospective analysis for Research and Applications Version 2 (MERRA-2) dataset to examine the relationships between aerosols and warm clouds in winter and explored the influence of meteorological conditions and different types of aerosols. There was a positive relationship between the aerosol optical depth and the cloud effective radius, cloud fraction and cloud optical thickness. However, the cloud top pressure tended to decrease with increasing aerosol optical depth. The influence of aerosols on warm clouds varied with the meteorological conditions. An analysis of the effects of thermal conditions, the vertical velocity and the relative humidity showed that stable atmospheric conditions, strong updrafts and a higher relative humidity increased the cloud fraction. Unstable atmospheric conditions and a high relative humidity also facilitated the formation of higher and thicker clouds. High sulfate aerosols were associated with moist air, a greater cloud fraction, a greater cloud optical thickness and a smaller cloud top pressure. Conversely, there was a smaller cloud fraction and cloud optical thickness and a greater cloud top pressure with drier air when there was a higher load of dust and black carbon aerosols.

关键词： Sichuan basin MERRA-2 Meteorological conditions aerosols Warm clouds

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Assessment of Infectious Diseases Risks From Dental aerosols in Real-World Settings

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OPEN FORUM INFECTIOUS DISEASES 2022年第11期9卷 ofac617页

作者： Choudhary, Shruti Bach, Tracey Wallace, Meghan A. Stoeckel, Daniel C. Thornhill, Martin H. Lockhart, Peter B. Kwon, Jennie H. Liang, Stephen Y. Burnham, Carey-Ann D. Biswas, Pratim Steinkamp, Heidi M. Durkin, Michael J. Univ Miami Dept Chem Environm & Mat Engn Aerosol & Air Qual Res Lab Miami FL USA Washington Univ Sch Med Div Infect Dis St Louis MO USA Washington Univ Sch Med Dept Pathol & Immunol St Louis MO USA St Louis Univ Ctr Adv Dent Educ St Louis MO USA Univ Sheffield Sch Clin Dent Sheffield England Atrium Hlth Carolinas Med Ctr Dept Oral Med Oral & Maxillofacial Surg Charlotte NC USA Washington Univ Sch Med Dept Emergency Med St. Louis MO USA Univ Iowa Coll Dent Dept Pediat Dent Iowa City IA USA Washington Univ Sch Med Div Infect Dis Campus Box 80514523 Clayton Ave St Louis MO 63110 USA

Background Infectious diseases physicians are leaders in assessing the health risks in a variety of community settings. An understudied area with substantial controversy is the safety of dental aerosols. Previous studies have used in vitro experimental designs and/or indirect measures to evaluate bacteria and viruses from dental surfaces. However, these findings may overestimate the occupational risks of dental aerosols. The purpose of this study was to directly measure dental aerosol composition to assess the health risks for dental healthcare personnel and patients. Methods We used a variety of aerosol instruments to capture and measure the bacterial, viral, and inorganic composition of aerosols during a variety of common dental procedures and in a variety of dental office layouts. Equipment was placed in close proximity to dentists during each procedure to best approximate the health risk hazards from the perspective of dental healthcare personnel. Devices used to capture aerosols were set at physiologic respiration rates. Oral suction devices were per the discretion of the dentist. Results We detected very few bacteria and no viruses in dental aerosols-regardless of office layout. The bacteria identified were most consistent with either environmental or oral microbiota, suggesting a low risk of transmission of viable pathogens from patients to dental healthcare personnel. When analyzing restorative procedures involving amalgam removal, we detected inorganic elements consistent with amalgam fillings. Conclusions aerosols generating from dental procedures pose a low health risk for bacterial and likely viral pathogens when common aerosol mitigation interventions, such as suction devices, are employed.

关键词： aerosols COVID-19 dentistry infection control infection prevention SARS-CoV-2

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Low Temperature Plasma Sources for Effective Inactivation of Pathogenic Microbial aerosols

Low Temperature Plasma Sources for Effective Inactivation of...

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2021 IEEE International Conference on Plasma Science, ICOPS 2021

作者： Liu, Dawei Huazhong University of Science and Technology State Key Lab of Advanced Electromagnetic Engineering and Technology School of Electrical and Electronic Engineering WuHan430074 China

ISBN: (纸本)9781665432276

In order to develop the LTP air filtration system which can effectively inactivate PMA, we studied the bioche mical mechanism of inactivating pathogenic microorganisms by LTP, and the physical process of charging and adsorption of PMA by LTP, and on this basis, we developed an efficient LTP source for effective inactivation of PMAs. The scalable prototype plasma air filtration system effectively killed all the bacteria within the inter cepted pathogenic aerosols. © 2021 IEEE.

关键词： aerosols

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Determination of four tobacco-specific nitrosamines in electronic cigarette liquids and aerosols by UPLC-QTOF-HRMS

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CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2024年第9期52卷

作者： Wang, Chunqiong Li, Wei Zeng, Yanbo Wu, Yongliang Chen, Dan Meng, Hongming Zhang, Ke Zhang, Xiaowei Li, Ganpeng Liu, Kai Yunnan Tobacco Qual Supervis & Test Stn Kunming 650106 Peoples R China Yunnan Minzu Univ Sch Ethn Med Key Lab Chem Ethn Med Resources State Ethn Affairs Commiss Kunming 650500 Peoples R China Yunnan Minzu Univ Minist Educ Kunming 650500 Peoples R China Guangdong Tobacco Qual Supervis & Test Stn Guangzhou 510610 Peoples R China

To elucidate the concentrations of four tobacco-specific nitrosamines (TSNAs) in commercial e-cigarettes, analyze the correlation between TSNAs and Nicotine, and clarify the main sources of TSNAs in e-cigarettes. Ultra-high performance liquid chromatography with quadrupole time-of-flight high-resolution mass spectrometry (UPLCQTOF-HRMS) was employed to determine the concentrations of four TSNAs in thirty-two commercially available e-cigarettes. The results demonstrated that the method exhibits excellent linearity and high mass accuracy. The limits of quantification (LOQ) of four TSNAs in e-cigarettes were 0.0010 -0.0165 (e-liquids) and 0.0032-0.0554 (aerosols) ng g (- 1) . The limits of detection (LOD) of four TSNAs in e-cigarettes were 0.0011-0.0165 (e-liquids) and 0.0033-0.0537 (aerosols) ng 20 puffs(-1 ). The recovery of four TSNAs ranged from 73.06 % to 109.95 %. The e-liquids contained: 0-33.970 (NNN), 0.063-15.654 (NNK), 0-10.033 (NAT), and 0-0.251 (NAB) ng (- 1 ). The aerosols contained: 0-60.662 (NNN), 0.021-9.435 (NNK), 0.202- 29.866 (NAT), and 0-2.841 (NAB) ng 20 puffs(-1). The correlation analysis results have shown that there was no significant correlation between the concentrations of four TSNAs and nicotine in e-cigarettes. The concentrations of four TSNAs in e-liquid containing tobacco extract were significantly higher than that in e-liquid without tobacco extract, suggested that the main source of TSNAs was tobacco extract. This method is fast, simple, highly sensitive, and has low detection limits. The approach taken can provide data support for the actual supervision of e-cigarettes, and evaluation of safety components, contributing to effective quality evaluation systems.

关键词： E-cigarette E-liquids aerosols TSNAs Concentration determination

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Characterization of aerosols in an Underground Mine during a Longwall Move

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MINING METALLURGY & EXPLORATION 2020年第4期37卷 1065-1078页

作者： Bugarski, Aleksandar D. Hummer, Jon A. Vanderslice, Shawn Shahan, Michael R. NIOSH Pittsburgh Min Res Div 626 Cochrans Mill Rd Pittsburgh PA 15236 USA

A study was conducted in an underground mine with the objective to identify, characterize, and source apportion airborne aerosols at the setup face and recovery room during longwall move operations. The focus was on contributions of diesel- and battery-powered heavy-duty vehicles used to transfer equipment between the depleted and new longwall panels and diesel-powered light-duty vehicles used to transport personnel and materials to various locations within the mine. aerosols at the setup face were found to be distributed among diesel combustion-generated submicrometer and mechanically generated coarse aerosols. According to the data, the submicrometer aerosols downstream of the setup face were sourced to diesel exhaust emitted by vehicles operated inside and outside of the panel. Depending on the intensity of the activities on the panel, the outby sources contributed between 12.5 and 99.6% to the average elemental carbon mass flow at the setup face and recovery room. Extensively used light-duty vehicles contributed measurably to the elemental carbon concentrations at the setup face. The number concentrations of aerosols downstream of the setup face were associated with aerosols generated by combustion in diesel engines operated in the shield haulage loop and/or outside of the longwall panels. Entrainment of road dust by diesel or battery-powered load-haul-dump vehicles operated near the measurement site appears to be the primary source of mass concentrations of aerosols. The findings of this study should help the underground mining industry in its efforts to reduce exposures of miners to diesel and coarse aerosols.

关键词： aerosols Diesel Dust Underground mining Longwall

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Effects of atmospheric aerosols on heat stress over South Asia

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ENVIRONMENTAL RESEARCH-CLIMATE 2023年第4期2卷 045007-045007页

作者： Ajay, Parottil Nair, Vijayakumar S. Babu, S. Suresh Das, Chiranjit Usha, K. H. Vikram Sarabhai Space Ctr Space Phys Lab Thiruvananthapuram India Natl Ctr Atmospher Res Boulder CO USA Indian Inst Technol Ctr Atmospher Sci New Delhi Delhi India

The recent trend in global mean temperature is expected to increase the frequency, duration, and intensity of heat waves and heat stress all around the world, especially over the Indian subcontinent. To investigate the plausible mechanisms and implications of meteorological feedback of aerosol forcing on heat stress over South Asia, simulations using a regional climate model (RegCM4) coupled with aerosols were carried out from 2015 to 2019. Generally, extreme heat days are observed mainly over the central and western Indo-Gangetic plains (IGPs) during May. The two heat-humidity indices, wet-bulb temperature (WBT) and heat index (HI), showed moderate effects due to aerosol forcing despite the high aerosol loading during the pre-monsoon. The inclusion of aerosols leads to surface cooling (a reduction in maximum surface temperature), with the highest impact over western India (WI) and the IGP. However, this surface cooling due to aerosols is compensated by an increase in near-surface relative humidity (RH), leading to an increase in WBT and HI. This compensating effect of RH on WBT and HI is greater in WI than that in eastern India. Regional heterogeneity in aerosol-induced changes in heat stress has a strong dependence on land-atmosphere interactions. This study clearly shows that aerosol-induced changes in RH play a decisive role in the assessment of heat stress, which answers the link between the prevalence of high heat stress conditions despite high aerosol loading (surface cooling) over the Indian region.

关键词： aerosols heat stress wet-bulb temperature South Asia

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Characterization of Bacteria on aerosols From Dust Events in Dakar, Senegal, West Africa

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GEOHEALTH 2020年第6期4卷 e2019GH000216页

作者： Marone, Alioune Kane, Coumba Toure Mbengue, Malick Jenkins, Gregory S. Niang, Demba Ndao Drame, Mamadou Simina Gernand, Jeremy M. Cheikh Anta Diop Univ Lab Appl Microbiol & Ind Engn Ecole Super Polytech ESP Dakar Senegal Epidemiol Surveillance & Training IRESSEF Inst Hlth Res Diamniadio Senegal Penn State Univ Dept Meteorol & Atmospher Sci University Pk PA 16802 USA Univ Cheikh Anta Diop Lab Atmospher Ocean Phys Simeon Fongang Ecole Super Polytech ESP Dakar Senegal Penn State Univ Dept Mineral Engn University Pk PA 16802 USA

We identify bacteria types on collected dust samples in Dakar Senegal, a region that experiences frequent Saharan dust events. We use classical techniques to identify bacteria types from dust samples. Seventy-seven bacteria types are identified from samples collected by spatula and the QuickTake (R) 30 air sampling pump. The dominant groups in the first batch of 51 bacteria (collected via deposition) are Micrococcus (33.33%), Bacillus (13.73%), Kytococcus (11.76%), Pseudomonas (9.80%), and Burkholderia (7.84%) and dominants in the second batch of 26 bacteria (collected with aerosol sampling vacuum pump): Pseudomonas (38.61%), Burkholderia (26.92%), Micrococcus (11.54%), and Brucella spp (7.69%). These bacteria are found in earlier studies from desert sources and can potentially cause respiratory diseases to exposed populations. Future work will use molecular methods is necessary to search for additional pathogens, including viruses on dust aerosols. Plain Language Summary Bacteria on the surfaces of Saharan dust samples collected from 2013-2016 were analyzed using traditional techniques at Dakar, Senegal. The samples were collected using a spatula and the QuickTake (R) 30 air sampling pump. The analysis finds some bacteria that are linked to respiratory disease, including Micrococcus, Burkholderia, and Pseudomonas. We believe that the spatula technique may include bacteria such as Bacillus from soils, which was not present in airborne samples. Additional analysis using genomic techniques will assist in better identifying bacteria and potential pathogens, which can impacts West African populations and are transported downstream over long distances to the Caribbean, Southeastern United States, South America, and Europe.

关键词： Sahara Senegal aerosols bacteria identification respiratory

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Tackling second-hand exposure to tobacco smoke and aerosols of electronic cigarettes: the TackSHS project protocol

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GACETA SANITARIA 2020年第1期34卷 77-82页

作者： Fernandez, Esteve Jose Lopez, Maria Gallus, Silvano Semple, Sean Clancy, Luke Behrakis, Panagiotis Ruprecht, Ario Gorini, Giuseppe Lopez-Nicolas, Angel Radu-Loghin, Cornel Soriano, Joan B. Inst Catala dOncol ICO Lhospitalet De Llobregat Barcelona Spain Inst dInvest Biomed Bellvitge IDIBELL Lhospitalet De Llobregat Barcelona Spain Univ Barcelona Sch Med & Hlth Sci Bellvitge Campus Lhospitalet De Llobregat Barcelona Spain Agencia Salut Publ Barcelona Barcelona Spain CIBER Epidemiol & Salud Publ CIBERESP Madrid Spain Inst dInvest Biomed St Pau IIB St Pau Barcelona Spain Ist Ric Farmacol Mario Negri IRCCS Milan Italy Univ Stirling Inst Social Mkt Stirling Scotland TobaccoFree Res Inst Ireland Dublin Ireland Hellen Canc Soc George D Behrakis Res Lab Athens Greece Fdn IRCCS Ist Nazl Tumori Milan Italy Ist Studio Prevenz & Rete Oncol Florence Italy Univ Politecn Cartagena Cartagena Spain European Network Smoking & Tobacco Prevent Brussels Belgium Hosp Univ La Princesa Resp Dept Madrid Spain

Objective: The TackSHS project aims to comprehensively elucidate the impact that exposure to second-hand smoke (SHS) from cigarettes and second-hand aerosols (SHA) from electronic cigarettes have on the respiratory health of the European population according to socioeconomic characteristics and other determinants. Method: The TackSHS project involves a series of coordinated studies carried out by 11 academic and public health organisations from six European countries. The project will investigate: a) the determinants of SHS and SHA exposure assessed at the individual level (surveys on representative general population samples) and in common environments (environmental sampling in specific settings): b) the overall disease burden, mortality and morbidity attributable to such exposure;and c) its economic impact in terms of direct health care costs. The project will also examine specific acute respiratory health changes in healthy individuals and patients with respiratoly diseases exposed to SHS and SHA. In addition, the project will examine the effectiveness of a novel intervention to reduce SHS exposure in households where smoking is permitted. All these studies are inter-related and involve collaborative coordination among the participant organisations. Conclusion: The comprehensive, integrated approach of the TackSHS project will enable a significant step forward from the current status quo in the understanding of the impact of SHS and SHA exposure on health and provide the basis for health policy recommendations to help European countries to further reduce the harm caused by SHS and SHA exposure. (C) 2019 SESPAS. Published by Elsevier Espana, S.L.U.

关键词： Second-hand smoke Passive smoking Electronic cigarette Electronic nicotine delivery systems aerosols Second-hand aerosols Respiratory health Burden of disease Economic impact

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